Performance Tuning :: Oracle Server - Analyze Table In Main Database
Jul 13, 2010
I have a procedure which mainly run queries on a Table which has nearly 9.5 million recodes. This procedures takes nearly 15 min to complete execution on our main database. I exported and imported the schema to our backup database and the same procedure just took 3 seconds to complete.
I tried to analyze the table in our main database and tried to execute the procedure again but did not show any improvements. ANALYZE TABLE DN_ACTIONS COMPUTE STATISTICS;
I am not sure computing the statistics for all the tables in the schema will work. I also checked there is enough disk space where oracle data files are stored. I am also turning on the sql trace to see what sql statements in the procedure is taking longer time.
I support to get a handle on statistics collectionn in their data warehouses. It seems developers have created several ANALYZE TABLE jobs but the code for these is not stored as PLSQL in the database and thus it is problematic for statistics collection. Even if we collect stats that way we want, these jobs kick in and overlay the statistics we collect every day.
Is there a way to AUDIT ANALYZE TABLE? I can't find it anywhere.
Is there a way to globally turn of ANALYZE TABLE in a 9i database?
I load a table through sql loader which takes nearly 14 min for 8-9 millions records, once the records complete i run the analyze table compute statics to gather stats and it takes nearly 15 min. is there any ways so that i can reduce the stats timing. the stats collection command runs from other schema not from where the table is residing.
We are using 11.2.0.3.0 on solaris 10 facing slow performance, following are the Wait Events in AWR report, Also if any specific document to analyze AWR report and to pin point the performance bottleneck.
Foreground Wait Events ********************** Avg %Time Total Wait wait Waits % DB Event Waits -outs Time (s) (ms) /txn time -------------------------- ------------ ----- ---------- ------- -------- ------ direct path read 308,729 0 21,191 69 58.0 39.5 db file sequential read 208,754 0 3,742 18 39.2 7.0 cursor: pin S 19,541,899 0 2,561 0 3,668.5 4.8 [code]....
I used v$locked_object and v$lock query to get the output.. But still I'm an one year exp in ORACLE. How to analyze the output of lock queries. what are the parameters to be analyzed on AWR report.
How to do proper performance checkup in ORACLE database as well analyze it.
By default the DBMS_STATS package runs once every 24 hours to collect statistics for database objects and Oracle collects new statistics when enough of the data (about 10%) has changed.
My question here is how to check the table has changed 10% in database?
I have a question regarding memory parameters in oracle database 9.2.0.8, especially sga_max_size and db_cache_size. Database server has 32G of ram. Oracle parameter on server shmmax is set to 16G. Is reasonable to set sga_max_size to the same value, and db_cache_size to 80% of that size?
I am querying v$sga and getting variable size : 211337216 bytes.when querying v$sgastat then getting
java Pool : 16777216 Large Pool : 41943040 Shared pool : 398560392
But as per my knowledge following condition should satisfy,but not getting
[code]
Variable sga = java pool + large pool + shared pool select pool,name,sum(bytes) from v$sgastat where pool in ('shared pool','java pool','large pool') group by pool,name;
Here variable size using v$sga : 211337216 bytes
and java pool + large pool + shared pool : 211302536 bytes.
I have a query optimized as to it indexes and others runs immediately when the answer is few records in SQL Server such as Oracle, however when the result is large eg 20,000 records all data access times are very diferent. The query returns many fields (about 20) and some of them are of type Varchar 250 and some of 2000 I understand here may be the problem, but not is because for similar results (20,000 records) sql run in 2 seconds and Oracle but it responds little to have full data takes around 30 seconds. The problem is really in bringing information to all these fields since if the inquiry it also but only returning a numeric field is done in 2 seconds. Tests I've done them both through ODBC, in the Toad as in the own Oracle console on the server, so it is not problem Driver or flow of data through the network, I would like to think that this is some of the settings I think there is as much difference between Oracle and Sql. The databases are ORACLE 10 and SQL Server 2008.
Looking to understand the difference between instance tuning and database tuning.
What is the difference between these two tuning exercises? I understand that an instance is memory based structures (logical) where as database consists of physical structures.
However, how does one tune a database the physical structure? Does it have to do with file placements/block sizes etc. Would you agree that a lot of that is taken care by ASM now in 11g? What tools are required/available (third party as well as oracle supplied) for these types of tuning scenarios?
Customer is sending data from legacy system (Source) with the web service which in turn calls a package lying on Oracle server (Target). Now this package is simply inserting data passed by legacy system into master staging table in Oracle database. When they started this process in Sept 2011 then 4 lack records were inserted into staging table. In Oct 11 it was 0 records Nov 11 it was 2 lack records, Dec 11 it was 1 lack records, in Jan 12 it was 1 lac records, Feb 12 73k records, Mar 12 0 records, Apr 12 52k records.
As we see that number of records inserted in the table got reduced with time.. what should be the starting point here since web service is calling that package on the fly, how can i enable trace for that package? I cannot replicate this is Dev as this process is only working in PROD.
There is a simple way to increase the performance of a query by reducing the row-size of the table it hits. I used it in the past by dividing the table into smaller parts and querying respective smaller table in each query.
what is this method called ? just forgot the method and can't recall it. what this type of row-reduction optimization is called ?
I have two tables with 113M records in DWH_BILL_DET & 103M in prd_rerate_chg_que and Im running following merge query, which is running for 13 hrs to update records, which is quiet longer time.
SQL> explain plan for MERGE /*+ parallel (rq, 16) */ INTO DWH_BILL_DET rq USING (SELECT rated_que_rowid, detail_rerate_flag_code, rerate_sel_key,
Testing our 9i to 11g upgrade, we've imported the entire DB into the new machine.We've found that certain procedures are really suffering performance problems. BUT, we've also found, that if we check out a production copy of the procedure from our source code control, and reinstall it, the performance issue goes away. Just alter the procedure and recompiling does NOT work.
The new machine where the 11g database exists is slightly different than the source, but it's not like we have this problem with every procedure. It's only a couple.
any possible reason that we'd have to re-install a procedure to correct a performance problem?
insight into the overheads for mutally authenticated SSL for database connections? This is over a fast local network, to a RAC cluster, with DB firewall in front. There's always a large element of "it depends"
Information I'm interested in are things like latency for initial session setup and subsequent data transfer. Also the increase in network packet size, and the increase in CPU cost for the database server. I guess there is some implications for session memory usage as well.
I have one big database which I need to migrate to Oracle, because it rocks with big databases, instead of other databases and when I was made transfer software and all works great except one more think. During this process I found that Oracle normally fill log & undo table, and my question is how to migrate (or can I migrate) database to oracle without filling undo database (deactivate this process) and after that to put database to work normally, because I just need to transfer data as is and from that point Oracle goes on...
i am using 11.2.0.3 version of oracle. We have recently migrated to 11g, after 1 month of smooth and comparatively better performance, we are suddenly facing performance issues with our database and it got crashed twice within 5 days. even we didnt push any new code to our database in recent past, atleast after the 11G migration. And after getting feedback from the ORACLE corporation guys , they pointed out about the default database stats gathering job, which was eating most of the CPU, because of the default degree mentioned So it was running in 160 parallel threads causing resource starvation.so we reduce the degree of the stats gathering job to 8 .
But the database crashed again two days back, and rebooted within 3 mins to back to normal, even after this default degree changed to 8. This is happening due to any specific application related sql or anything else.
I am doing import and export of database.Before loading data i drop all the tables and import.Is there any issue if we do drop tables and import data frequently.
I understand that when data is read from the disk, I/O is done..And When computations are done then CPU is used..Then where the following equation fits?
we are using oracle 9i on AIX Server. When Customer were accessing the database, accidentally power was shut down. we restarted the Server,and Oracle database. all resumed successfully.
However while doing "Payments by the customer" it takes a lot of time to insert even a single payment record on database.The database is Live and our customer are very much frustrated,
I am trying to update columns of Table A with the columns of Table B. Both these tables have 60,000 rows each. I tried this operation using following 2 queries:
Query 1
Update TableA A set (A.col1,A.col2,A.col3)=(select B.col1,B.col2,B.col3 from TableB where A.CODE=B.CODE)
Query 2 Update TableA A set (A.col1,A.col2,A.col3)=(select B.col1,B.col2,B.col3 from TableB where A.CODE=B.CODE) where exists A.code = (select B.code from TableB B where A.code=B.code)
When i execute these two above queries, it keeps executing indefinitely.
select gam.SOL_ID,COUNT(gam.FORACID) from gam,smt where gam.ACID=smt.ACID and gam.ACID NOT IN(select ACID from imt) and gam.SCHM_TYPE in('SBA','CCA','CAA','ODA') and GAM.ACCT_CLS_FLG='N' and gam.SOL_ID IN(select SOL_ID from IMT) group by gam.SOL_ID /
attached is the explain plan.
in which index on IMT table is not used. And the query is doing a FTS on IMT table. What needs to be done to avoid FTS on IMT table.
NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ lock_sga boolean FALSE pre_page_sga boolean FALSE sga_max_size big integer 1152M sga_target big integer 0
[code]....
in scenario above, the database do not using ASMM, and spfile If I wan to increase db_cache_size parameter, do i need to rebounce instance?
I am facing a weird situation wherein the explain plan of same sql in SIT and PROD is different.In fact the explain plan is very costly in Prod.Also the DB version of both SIT and PROD is same.
Below is the sql and corresponding explain plan in Prod and SIT respectively.
Query: SELECT seq,CCN,ProcessorPart,root_item,comp_path,Item,comp_item,comp_item_type, lag(comp_item_type,1,'PART') over(PARTITION BY seq ORDER BY lvl)Nxt_comp_item_type,lvl,bom_qty, ROUND(CASE min(abs(bom_qty)) OVER (PARTITION BY seq ORDER BY lvl) WHEN 0 THEN 0 ELSE 1 END * EXP (SUM (LN (nullif(abs(bom_qty),0))) OVER (PARTITION BY seq ORDER BY lvl))) Ulti_qty, 'AMER'
[code]...
The tables referred in above query is small tables containing arnd 10k records.The above tables are partitioned on Region and not indexed.
I am not able to attribute why there is a huge change in Cost between SIT and Prod.Apparently the Job is going for 3-5 hours which used to get completed within 20mins in SIT.
